In the prior art, if a driver leaves the engine running in the automotive vehicle for a long time, the doors may be locked by using a spare key different from the key inserted into the ignition switch or by using a transmitter of a keyless entry system in order to prevent the automotive vehicle from being stolen or the like. The engine may be left on to keep the air conditioner in operation to maintain the temperature inside of the automotive vehicle or to warm up the engine by an idling operation to obtain stable running characteristics from a starting time.
However, since the spare key, which is different from the key or the transmitter of a keyless entry system, is necessary, it is troublesome to manage the keys.
Also, if window glass is broken to unlock the automotive vehicle, since the key is left in the ignition switch, the automotive vehicle is easily stolen by the usual drive operation.
In view of the foregoing circumstances, it is an object of the present invention to provide a keyless engine controlling unit where a driver can leave the automotive vehicle by locking an opening/closing means such as a door by using a key. The key is not left in the automotive vehicle. This prevents the vehicle from being stolen and also easily supervises the key without a special spare key.